Device for mixing and impelling of heat-exchange fluids

ABSTRACT

A wall means defines a first, a second and a third chamber. An impeller is interposed between the first and the second chambers and has a suction side communicating with the first chamber and a pressure side communicating with the second chamber. An outlet communicates with the second chamber and with a user. A pair of inlets for cooler and hotter fluid each communicate with one of the first and third chambers, respectively. A pair of axially aligned apertures connects the first and third chambers with one another. A tubular baffle is shiftable axially in the apertures for increasing the effective cross-section of one of the apertures while simultaneously decreasing the effective cross section of the other aperture, and vice versa.

United States Patent 1 Mar-n July 8, 1975 [54] DEVICE FOR MIXING AND IMPELLING OF 343,385 2/1931 United Kingdom H 415/199 4;

HEAT EXCHANGE FLUIDS 636,848 5/1950 United Kingdom 415/5 326,866 /1920 Germany 415/157 Inventor: Edmund Maron, Steinach,

Switzerland [73] Assignee: Aktiengesellschaft Adolph Saurer, Primary Emmmer l'1emy Raduazo Arbon, Switzerland Attorney, Agent, or Firm-Michael S. Strlker [22] Filed: Aug. 31, I973 [21] App]. No: 393,681 57 ABSTRACT 30 Foreign Application Priority Data s s defilllies fi a s g and a flgird c am er. n impe er 1s mterpose etween t e irst Sept. 5, 1972 Switzerland 13028/72 and the Seccmd m e s nd has a Suction Side com- [52] U 5 Cl 415/157, 415/] 415/53 rnunicating with the first chamber and a pressure side [5|] F04d 31/00 communicating with the second chamber. An outlet [58] Fieid 53 communicates with the second chamber and with a 6 i' 199 R user. A pair of inlets for cooler and hotter fluid each communicate with one of the first and third chambers,

d respectively. A pair of axially aligned apertures con- [56] gg gz nects the first and third chambers with one another. A UNITED STA tubular baffle is shiftable axially in the apertures for 2,2 SZYOHOWSkl t a1. increasing the effective cross section of one of the ap- 2,496,870 2/1950 I "415/11 ertures while simultaneously decreasing the effective cross section of the other aperture, and vice versa. FOREIGN PATENTS 0R APPLICATIONS 6 Claims 2 Drawing Figures 530,088 9/1921 France 415/157 I)Ii\ ICIL FOR MIXING AND IMI'ELLINU OF HIiAT-EXFHANUE FLUIDS BACKGROUND OF THE INVENTION The present imention relates generally to a device for mixing and impelling of heat-exchange fluids. particularly for heat-exchange fluids in central heating systents and the like.

It is know n. for instance. in central heating systems. to use an impeller pump the suction side of which is connected to a supply conduit which receives a mixture of hot and cool fluid from a mixing valve. the connec tion being made with the conduit at some distance from the mixing valve. Evidently. this type of construction requires the use of a conduit section with appropriate sealing surfaces and Increases the space requirements for the arrangement. aside from the fact that it makes the installation of the system more difficult.

It has been proposed in the prior art to combine the housing of the mixing valve and of the impeller pump into a single unit. that is a ttnit having a single housing with the mixing chamber of the mixing valve acting simultaneously also as the suction chamber of the pump. this type of mixing valve uses a rotary rod member which can be manually operated from the exterior of the ab e and which serves to vary the proportion of hot and cool fluid that is being admitted in the valve. Unfortunately. there is no way in which this type of valve can be automatically adjusted in a simple manner. Evidently. it is possible to devise an arrangement which would permit such adjustment. but such an arrangement would have to be rather complicated and expensl\t.. aside from the fact that the more complicated the arrangement would he the more it would he subject to malfunction. This is particularly true since for the sake of simplicity. the automatic thermodynamic drive for such a purpose should afford a linear movement which would have to be com erted by a complicated arrange ment into a rotary movement capable of turning the vahe member.

SUMMARY OF THE INVENTION It is. accordingly. an object of the present invention to provide an improved device. of the type under discussion which is much simpler and less complicated than what is known from the prior art.

More particularly. it is an object ofthe present inven tion to provide an improved device for mixing and impelling of heat-exchange fluids which is not hossessed of thc disad\ antages outlined with respect to the prior art.

In keeping with the above objects. and with others which will become apparent hereafter. one feature of the imention resides. in a device for mixing and impelling of heat-exchange fluids. in a combination comprising wall means defining a first. a second and a third chamber. An impeller is interposed between the first and second chambers and has a suction side communicating with the first chamber. and a pressure side communicating with the second chamber. An outlet communicates with the second and with a user. A pair of inlets for cooler or hotter heatexchangc fluids each communicate with one of the first and third chambers. respectively. A pair of axially aligned apertures connect the first and second chambers with one another. Tubular baffle means is shiftable axially in the aper tures and operative for increasing the effective crosssection ofone of the apertures while simultaneously decreasisng the effective cross-section of the other aper turc. and vice versa.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claaims. The invention itself. however. both as to its construction and its method of operation. together with additional objects and advantages thereof. will be best understood from the following de scription of specific embodiments w hen read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING FIG. I is a somewhat diagrammatic and fragmentary axial section through an embodiment of the present invention; and

FIG. 2 is a section taken on line H of FIG. I. simplified in certain respects for the sake of clarity.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Discussing the drawing in detail. and keeping in mind that it shows a single exemplary embodiment of the invention. it will be seen that reference numeral I the pump housing of a centrifugal pump. Secured to that pump housing and known. is an electromotor having an output shaft 3 on which there is mounted for rotation with the shaft 3 an impeller 4. The pump housing I has a partition wall 5 provided with a cov er 6 which permits access to the interior of the housing I, for initial manufacturing purposes as well as for subsequent inspection andfor repair purposes. The cover 6 constitutes. to gether with the shield of the electromotor 2 and the flange ofthe pump housing I which supports the elece tromotor 2. a pressure chamber 7 of the pump. This is a second chamber in the sense of the claim terminology employed herein. and it communicates with an outlet 8 which leads to a non-illustrated user.

The partition wall 5 with the cover 6 define with an additional partition wall 9 of the housing I a further space III. which communicates via an aperture A. with a chamber I7. which is the suction chamber of the pump. In fact. the space I0 may be considered a part of the suction chamber 17. which can also be thought of as the first chamber within the sense of the claim terminology employed in the appended claims. An inlet 11 communicates with the space 10 and receives cooler heat-exchange fluid. for instance. via a return conduit communicating with a user from which the cooled-off spent heat-exchange fluid is received. The passage or aperture A can be at least almost completely closed by means of a tubular baffle 12 which is in axial alignment with the axis of rotation of the shaft 3 and can be shifted by means of a shifting rod I3 in the direction of the double headed arrow I4. When the baffle is in the Iefthand position (which is not shown in FIG. It its Ieft-hand free end is pressed against the cover 6.

The baffle 12 is connected via spokes 18 with a center portion 19 which mounts in on the rod IS. The rod 13 in turn is shiftable in the direction of the aforementioned double-headed arrow I4 by a non'illustrated drive.

The partition wall 9 is formed with an opening or apcrture A: through which the baffle I2 extends. Together with the outer wall I5. through which the shaft I3 extends in sealing relationship (see the illustrated seal the partition wall 9 defines a further chamber 16 which may be thought of as the third chamber of the claim terminology. The chamber 16 communicates with an inlet 21 through which it receives hot heatexchange fluid. for instance from a boiler or the like. Depending upon the direction in which the tubular baffle 12 is displaced by axial shifting of the rod 13 in the direction ofthe arrow l4. the baffle l2 can either close or at least reduce the effective cross-section of the aperture A, to thereby more or less separate the space H) from the chamber 17. until finally. the left-hand free end of the baffle l2 engages the cover 6. or the baffle can more or less close or reduce the effective crosssection of the aperture A until finally. the right-hand end of the baffle 12 engages the wall 15. as shown in FIG. 1. Of course. as the effective cross-section of the apertures A, or A increases. the effective crosssection of the other aperture A: or A, will simulta neously increase. The outer cylinder or circumferential surface of the baffle 12 is provided with a lip-sealing ring 20 which in the illustrated embodiment is of l.- shaped crosssection. When the baffle I2 is in the positon shown in FIG. I. in which the chamber 16 is cut-off from the chamber l7. the upstanding flange of the seal 20 abuts against the inner side of the partition wall 9 in sealing relationship.

It is desirable that the axial length of the overall device be as small as possible. For this purpose the impeller is located as close to the wall at the side of the pressure chamber 7. as the deflection of the heatexchange fluid which moves in primarily radial di rection out ofthe space into the suction chamber 17 permits without incurring excessively high pressure losses.

The connection of the inlets It and 21 with the spaces HI and 16 could of course be exchanged. if desired. as long as the sealing ring is appropriately arranged and the direction of movement of the baffle is reversed The ring 20 must prevent any escape of fluid from the chamber 16 when the baffle 15 Is in the posi tion shown in FIG. 1. that is when it abuts with its right hand axial end the wall 15. This is the position in which the user does not require any heated fluid.

The particular configuration. particularly crosssectional configuration chosen for the ring 2" has the advantage that the latter can be reliably mounted without any difficulties and in a very simple manner in a circumferential groove formed in the outer surface of the baffle 12. and that its upstanding projection is suffi ciently resistant to deflection to provide a proper seal with respect to the partition 9.

With this arrangement it is possible to install a temperature sensor in the pump hosuing l. in such a manner that its sensing component extends into the pressure chamber 7. Thermal insulating means 25 is pro vided which thermally insulates the sensor 22 from the housing 1. Such insulating material is too well known to require detailed description.

H0. 2 shows that the impeller housing portion is of annular configuration. that is that the chamber 7 is also of annular configuration. and that the temperature sensor 22 is located directly adjacent the radially outer most inner wall 26 of the annular housing portion. within an angle range of l80 as seen with respect to the direction of rotation of the impeller 4. downstream of the inner edge 23 defined by the downstream side wall bounding the outlet 8 and the housing wall 20. When the sensor 22 is so located. it will be intensively surrounded and bathed by heat-exchange fluid in highly turbulent condition. so that it pro\ides for very sensitive and accurate indications of the temperature of admixed hot and cooler heat-exchange fluid. The instilation 25. on the other hand assures that the temperature of the housing does not influence the measurements taken by the sensing component 24.

The present invention recognizes and utilizes the trend in the construction of pumps or circulators for heating use. to employ an annular housing rather than a spiral housing for the impeller 4. because annular housings are less expensive to produce.

The manner in which the sensor 22 is mounted on or in the housing 1 has the further advantage that the electronic component with which the sensor 22 is to be connected. and which serves to control the drive for the displacement of the rod I3 in the direction of the double-headed arrow 14. can also be mounted on the housing 1 so that particularly compact and complete unit can be produced. Such units are greatly prized by firms installing heating equipment because they reduce substantially the amount of installation time.

Merely for the sake of completeness. l have illustrated in HG. 2 in chain lines the form of another pump housing which could also be employed instead of the annular housing shown. This secondary housing is more expensive to produce. but is more advantageous from a point of fluid flow. The possibility has been illustrated to indicate that when the sensor 22 is installed in the manner described herein. it will not significantly influence the fluid flow and therefore pressure losses.

lt will be understood that each of the elements de scribed above. or two or more together. may also find a useful application in other types of constructions dil fering from the types described above.

While the invention has been illustrated and dc scribed as embodied in a device for mixing and impel ling of heat-exchange fluids. it is not intended to be limited to the details shown. since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis. the foregoing will so fully reveal the gist of the present invention that others can be applying current knowledge. readily adapt it for various applications without omitting features that. from the standpoint of prior art. fairly constitute essential characteristics of the generic or specific aspects of this invention and therefore. such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claim:

1. lit a device for mixing and impelling of heatexchange fluids. a combination comprising wall means defining a first. a second and a third chamber; an impel ler interposed between said first and second chamber and bin ing a suction side adapted to communicate with said first and said third chamber. and a pressure side communicating with said second chamber: and outlet communicating with said second chamber and with a user; a pair of inlets for cooler or hotter heat-exchange fluid each communicating with one of said first and third chambers. respectively; a pair of axially aligned aperture axially spaced from said suction side of said impeller and connecting said first and third chambers with one another; and tubular baffle means shiftable axially in said apertures and operative for increasing the effectne cross-section of one ol said apertures while simultaneousl LlLLlCtlNlllg the cl'lcctne cross section of the other aperture. and vice \ersa 2. A combination as defined in claim l. wherein said impeller is rotatahle about an axis which is coincident with a longitudinal ;t\is of said tuhular hall'lc means 3. A combination as defined in claim I. said tubular baffle means haflng an outer c lindrical circuniten ence; and further comprising a lip-seal ol substantial! L-shaped cross-section mounted on said circumter' ence.

4. A combination as defined in claim 1; and further comprising a temperature sensor projecting through said wall means into said second chamber; and thermal ill 6 insulating means thcrmall insulating said sensor \iitli respect to said wall means.

5. A combination as defined in claim 4. llcl'CIH said second chamber is annular 6. A combination as defined in claim 5. wherein said outlet is bounded by a first edge and h an opposite second edge which is spaced from said first edge in dircction of rotation of said impeller; and wherein said tem erature sensor projects into said second chamber in a region included in an angle of up to 180 extending from said second edge circumferentially of said annular second chamber in said direction of rotation. 

1. In a device for mixing and impelling of heat-exchange fluids, a combination comprising wall means defining a first, a second and a third chamber; an impeller interposed between said first and second chamber and having a suction side adapted to communicate with said first and said third chamber, and a pressure side communicating with said second chamber; and outlet communicating with said second chamber and with a user; a pair of inlets for cooler or hotter heat-exchange fluid each communicating with one of said first and third chambers, respectively; a pair of axially aligned apertures axially spaced from said suction side of said impeller and connecting said first and third chambers with one another; and tubular baffle means shiftable axially in said apertures and operative for increasing the effective cross-section of one of said apertures while simultaneously decreasing the effective cross-section of the other aperture, and vice versa.
 2. A combination as defined in claim 1, wherein said impeller is rotatable about an axis which is coincident with a longitudinal axis of said tubular baffle means.
 3. A combination as defined in claim 1, said tubular baffle means having an outer cylindrical circumference; and further comprising a lip-seal of substantially L-shaped cross-section mounted on said circumference.
 4. A combination as defined in claim 1; and further comprising a temperature sensor projecting through said wall means into said second chamber; and thermal insulating means thermally insulating said sensor with respect to said wall means.
 5. A combination as defined in claim 4, wherein said second chamber is annular.
 6. A combInation as defined in claim 5, wherein said outlet is bounded by a first edge and by an opposite second edge which is spaced from said first edge in direction of rotation of said impeller; and wherein said temperature sensor projects into said second chamber in a region included in an angle of up to 180* extending from said second edge circumferentially of said annular second chamber in said direction of rotation. 